Thread veins (spider veins): causes, treatment and what the NHS offers

Thread veins do not need treatment to protect your health, so the choice is mostly about how much they bother you. If you do want them treated, a private hospital provider describes three main approaches. The practitioner recommends one according to the size, colour and location of the veins and your skin tone, and some people have a combination.

Whichever method is used, more than one session is usually needed for the best results. Treatment is done as an outpatient appointment with no overnight stay.

Thread veins are very small, visible veins just under the skin. They often show as fine red, blue, purple or pink lines, sometimes forming a web or branching pattern, which is why they are also called spider veins. They are most often noticed on the legs and face, and less commonly on the body.

For most people they cause no physical symptoms. They can still affect confidence, which is the usual reason people look into treatment.

The two are often confused, but they are managed differently. The NHS says varicose veins are widened veins that look swollen and twisted under the skin and may feel lumpy and bulge out, and that they are different from spider veins or thread veins. Varicose veins can cause aching, heaviness, itching and swollen ankles, and the NHS says a GP may refer you for tests and treatment if you have symptoms or complications such as leg ulcers.

The sources used for this guide do not give a full list of causes, and the reasons probably vary between people and body areas. A private provider links thread veins on the legs to a weakened one-way valve inside the vein, which lets blood pool so that the vein branches out.

On the face, visible small blood vessels can be part of rosacea. The NHS says rosacea may cause tiny broken blood vessels to appear on the skin that do not go away, and the British Association of Dermatologists says redness and dilated blood vessels in rosacea can be treated with laser therapy by a dermatologist. If your facial veins come with flushing, bumps or spots, it is worth asking a GP or pharmacist about rosacea.

If a doctor suspects the visible veins reflect a deeper circulation problem in the legs, a scan may be suggested. The provider explains that a scan to check the deeper leg veins may be done before treatment, and that if an underlying vein problem is found you would be guided towards varicose vein treatment instead.

The provider describes sclerotherapy as an outpatient procedure without cuts or anaesthetic. You may feel a brief cramping or burning sensation lasting a few seconds as each injection is given. Pressure is applied over the vein straight afterwards, and a compression stocking or dressing is applied before you go home, usually worn for about a week.

Most people return to normal activities straight away, though the provider suggests avoiding swimming, horse riding and heavy weightlifting for about a week and keeping legs raised when resting for the first few days. Some improvement is often visible quickly, but full results typically take several weeks and up to 2 months.

Possible side effects include bruising, redness, itching or swelling that usually settles within days, small firm lumps, and skin discolouration that can take weeks to months to fade. Bruising can occasionally last up to 3 months. Rarely, there is an allergic reaction to the solution or a blood clot. Ask the practitioner about their experience and what a realistic result looks like before you start.

Because thread veins are not dangerous, some people choose to do nothing. The sources do not describe them fading by themselves, so it is best not to expect it.

The provider says creams and gels marketed for thread veins do not remove them, whatever they claim, and that fake tan is best avoided over the area because it can cause brown discolouration of the skin as thread veins break down. The NHS advice on varicose veins, which is aimed at the larger problem, suggests keeping to a healthy weight, putting your legs up when possible, exercising regularly and not standing or sitting for long periods. These are sensible general measures for leg circulation, though they are not a treatment for thread veins.

NHS Scotland lists thread veins among procedures not routinely provided. Its referral protocol says treatment is only supported for severe conditions such as severe erythrotelangiectatic rosacea or arborising telangiectasia, judged by a regional vetting panel, that formal medical photography is required, and that a maximum of 6 treatment sessions will be offered. It also warns that treatment may lead to incomplete resolution. Arrangements elsewhere in the UK are set locally, so a GP can tell you what applies in your area.

Because most thread vein treatment is considered cosmetic, many people pay privately. In general it is sensible to check the practitioner's qualifications, whether a scan of the deeper veins is included when appropriate, how many sessions are expected and what happens if you are unhappy with the result.

Thread veins on their own are not usually a medical concern. The NHS advice on varicose veins says to see a GP if you have symptoms such as pain, itching or swelling in your legs, a sore on your leg that has not healed after 2 weeks, or if the veins are getting worse.

The NHS says to ask for an urgent GP appointment or get help from NHS 111 if varicose veins are bleeding.